Inter's Scudetto challenge was dealt another blow as they had to cling on for a 0-0 draw against Lazio at San Siro on Saturday.
A fourth successive Serie A match without a win has seen Inter, who were the early pacesetters following a 16-game unbeaten run, slide to third, with the gap to leaders Napoli now standing at seven points.
It could have been even worse, too. Lazio thought they had been given a glorious opportunity to take the lead when official Gianluca Rocchi awarded a penalty for handball against Milan Skriniar in the second half, but that decision was overturned after he had consulted the video assistant referee (VAR) system.
The Nerazzurri had their chances as well. Ivan Perisic - making his 100th Inter appearance in all competitions - was kept out from 10 yards by the brilliant Thomas Strakosha, who turned a shot from Borja Valero against the post in the second half.
Lazio substitute Felipe Anderson fired two great openings wide as Simone Inzaghi's side pushed for a winner that would have sent them level with fourth-placed Roma.
Chances were at a premium during an even start to proceedings, with Luis Alberto and Ciro Immobile unable to make the most of swift counter-attacks that pulled Inter apart.
18' All square in the early exchanges as the teams continue to work one another out. Few early chances. 0-0 December 30, 2017
When the Nerazzurri finally created a chance of their own in the 19th minute, Antonio Candreva was unable to rise high enough to nod a cross from Perisic beyond Strakosha.
Lazio immediately responded and Sergej Milinkovic-Savic - heavily linked with a move to Manchester United in the January transfer window - had a thumping 20-yard effort turned around the post by Samir Handanovic, before Bastos steered a free header over from the resulting corner.
Perisic went close to putting Inter ahead in the 30th minute, only for Strakosha to react excellently and tip his half-volley from Valero's cross behind.
There was nothing Handanovic could do when Valero looped a header over him when defending a corner in first-half stoppage time, but the crossbar stopped the Spaniard netting an embarrassing own goal.
Valero hit the woodwork at the other end 12 minutes after the restart, a fierce drive from the edge of the area pushed onto the upright by the diving Strakosha.
Lazio continued to threaten on the break and referee Rocchi initially gave a penalty when Skriniar's block on an Immobile cross ricocheted onto his arm, but after a VAR referral the handball was deemed to be accidental.
The visitors pushed for a winner and Felipe Anderson – a 65th-minute replacement for Alberto – burst into the box and flashed a shot wide of the far post as the clock ticked down.
A swift break after Joao Mario ceded possession nine minutes from time ended with Immobile crossing for Felipe Anderson, who missed the target from 10 yards.
Perisic wasted a final chance for Inter when he headed straight at Strakosha, with their recent difficulties in front of goal showing no sign of letting up.
